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Biomedical subjects

P Wuisman

Publications and source records attributed to P Wuisman.

At least 19 recordsLinked to original sources
PubMed1997

Intramedullary, antibiotic-loaded cemented, massive allografts for skeletal reconstruction. 26 cases compared with 19 uncemented allografts.

We compared the outcomes of 26 intramedullary cemented massive allografts with 19 allografts without cementation; all allografts were used for reconstruction after excision of bone sarcomas. In the cementation group, 12 allografts were used as osteochondral grafts (proximal humerus 4, proximal tibia 4, and distal femur 4), 7 as intercalary diaphyseal allografts of the femur, and 7 for a knee arthrodesis. In the uncemented allografts, 3 allografts were used as osteochondral grafts (proximal humerus 2, proximal tibia 1), 2 as intercalary diaphyseal allograft of the femur, and 14 for a knee arthrodesis. The average length of follow-up was 40 (25-60) months. 14 of 26 cemented allografts had an excellent (osteotomy line: not visible) or good (fusion > or = 75% of the cortical thickness) healing of the junction site. Infection developed in 1 allograft. Fracture occurred in 4 of 12 cemented osteochondral allografts due to a subchondral collapse (all in the proximal tibia). Fractures at the junction site in the lower extremity developed in 4 of 22 cemented allografts. In 19 allografts without cementation, 11 had excellent or good healing of the junction. Late infection developed in 4 allografts, fracture of the allograft in 3 cases, and junction fracture in 3 of 17 patients with reconstruction of the lower extremity. Intramedullary graft cementation seems to reduce the fracture and infection rates.

Adolescent↗
PubMed1997

Reconstruction of tibia by ipsilateral vascularized fibula and allograft. 12 cases with malignant bone tumors.

We treated 12 patients with a primary sarcoma of the tibia by resection and centralization of the ipsilateral vascularized fibula with preserved vascularization. The reconstruction was combined with an allograft. The median bone defect after tumor resection was 14 (8-24) cm. The anastomosis between the allograft and the recipient bone was stabilized by a plate or screws or Kirschner-wires. To reconstruct the soft tissues, 8 patients underwent a gastrocnemius plasty and 2 patients a free vascularized flap of the latissimus dorsi muscle. The mean follow-up period was 2.5 (2-3.5) years. 2 years after implantation, union > or = 75% of the anastomosis area was noted in 10 patients. A deformity or fracture of the distal junction occurred in 7 patients with a screw or Kirschner-wire fixation. Neither deformity nor fracture developed in the 5 patients with plate-fixation.

Adolescent↗
PubMed1996

In vivo 31P NMR spectroscopy of human musculoskeletal tumors as a measure of response to chemotherapy.

The value of in vivo 31P NMR spectroscopy to provide indicators of response to cytostatic chemotherapy was studied in patients with malignant musculoskeletal tumors. Characteristics of untreated cancers were strong signals of PME and PDE, moderately increased Pi and low PCr. The intracellular pH was slightly alkaline. The intracellular concentration of free magnesium was 70% of that in muscle. Spectroscopic findings at different times of therapy were compared with the percentage of tumor necrosis after surgical resection in 28 patients. In follow-up studies, energy-rich phosphates declined in nonresponders, while PME, Pi and frequently PDE increased. Treatment response appeared to involve the reversal of these trends. In five responders, a biphasic pattern was observed, i.e. initially the spectrum changed into that of severely ischemic cell injury followed by a successive phase of apparent 'tumor activation'. Pretreatment levels of (PCr+Pi)/total phosphate > or = 0.35 and PCr/ alpha-NTP > or = 1.5, an accelerated increase in total low-energy phosphates/total high-energy phosphates (> or = 3.0%/day) after the initial drug application, and a long-term decrease (< or = -0.4%/day) during later therapy were highly indicative of tumor response to chemotherapy. Such spectroscopic predictors for treatment response proved to be superior to currently used indices such as tumor size.

Adolescent↗
PubMed1996

High complication rates with pelvic allografts. Experience of 22 sarcoma resections.

We performed 22 reconstructions by allografts in patients with pelvic sarcoma: 14 Ewing's sarcomas, 7 chondrosarcomas, and 1 osteosarcoma. All patients with Ewing's sarcoma and osteosarcoma received chemotherapy. No patients with chondrosarcoma had adjuvant treatment. 12 reconstructions were iliosacral arthrodesis after resection of an ilium tumor, 1 was iliofemoral arthrodesis and 9 were pelvic reconstructions with total hip prosthesis after resection of an acetabulum tumor. In the surviving patients, the mean length of follow-up was 4 (2-6) years. 2 allografts fractured and 8 allografts developed an infection. The infection was commoner in patients who had chondrosarcomas, large tumors, and a long operation time. Neither chemotherapy nor radiotherapy increased the infection rate. All infected allografts had to be removed.

Adolescent↗
PubMed1994

Periosteal Ewing sarcoma.

PURPOSE: To evaluate the imaging and histopathologic findings and clinical course of patients with periosteal Ewing sarcoma (PES). MATERIALS AND METHODS: Conventional radiographs, computed tomographic (CT) scans, and magnetic resonance (MR) images in 10 adolescents and one adult were evaluated for the extent and character of PES. RESULTS: Ten of 11 masses were in the proximal extremities and one in the fibula; nine were diaphyseal and two, metadiaphyseal. Radiographs and CT scans showed a subperiosteal mass that did not invade the medullary cavity, was contiguous with and elevated the periosteum, and produced a Codman triangle and periosteal reaction. No PES exhibited osseous or cartilaginous matrix calcifications. MR imaging and histopathologic examination helped confirm the sparing of cancellous bone and the subperiosteal location. CONCLUSION: PES differs from the more common medullary and soft-tissue Ewing sarcomas in location, marked male predominance, and lack of presenting metastases. Except for the absence of matrix calcifications, PES resembles other periosteal sarcomas in imaging characteristics and a less aggressive clinical course.

Adolescent↗
PubMed1994

[Blood vessel transfer allowing avoidance of surgical rotation or amputation in the management of primary malignant tumors of the knee].

PURPOSE OF STUDY: The surgical and clinical outcome of a limb-salvaging technique for tumors about the knee utilizing autogenous vessel transfer is reported. The original indication for these lesions was amputation or Van Nes rotationplasty because of vascular encasement by the tumor. MATERIAL: Twelve patients are reported: seven females and five males with an average age of 16 years. There were nine distal femur and three proximal fibula stage IIB primary malignant tumors. METHOD: All patients underwent a local wide resection of the primary tumor including the main vessels, followed by local reconstruction of the bone and vessels by an ipsilateral vessel transfer. Postoperatively the limbs were immobilized in a cast and the patients were treated with intravenous Heparin, followed by a single low dose Heparin injection for three months. RESULTS: Immediate postoperative arterial occlusion in one patient was successfully treated, but eight weeks later another occlusion occurred and an amputation was necessary. In another patient, arterial thrombi necrotized two toes; they were subsequently amputated. Other local complications were hematoma (two patients), superficial skin necrosis (one patient), and deep infection (one patient). All were successfully revised surgically. All resections obtained negative margins, and there were no local recurrences or distant metastases. In all twelve patients the tumor either encased the artery and vein, or the pseudocapsule of the tumor touched the vascular adventitia. DISCUSSION: The results show that by patients in whom there is attachment of the tumor with major vessels or in whom the vessels are encased by the tumor, wide limb-saving resection can be achieved by en-bloc resection of the primary tumor and the vessels. In this respect a contamination of the vessels is no longer a contra-indication for a limb-saving procedure. CONCLUSION: The described method is safe, has a relatively low complication rate comparable with rotationplasties and allows a limb-saving procedure.

Adolescent↗
PubMed1994

[MRI in soft tissue tumors].

MRI has been shown to be very useful in the diagnostic work-up of soft tissue masses. Because of its multiplanar capability and excellent contrast resolution, MRI is the method of choice for identification of tumour extent and follow-up examinations of soft tissue lesions. Due to the unspecific appearance of most soft tissue tumours, MRI cannot replace biopsy for definitive determinations of the nature of the lesion (benign vs malignant) in the majority of cases.

Diagnosis, Differential↗
PubMed1994

[Reconstruction possibilities following resection of malignant musculoskeletal tumors].

Great advances have been achieved in the treatment of musculoskeletal tumors, and as a result limb-conserving resection is now possible in most cases. These advances are based on adjuvant therapy, development of histological criteria, new surgical techniques, and improved imaging methods. The use of computed tomography and magnetic resonance imaging has allowed more accurate preoperative staging. At the same time, an improvement in prognosis has also been achieved. After resection of the tumor, the following methods of reconstruction are available: reconstruction with no implant, endoprosthetic replacement, autogenous grafting, and allograft replacement. Postoperative monitoring is performed with plain-film radiography.

Bone Neoplasms↗
PubMed1993

Chondromyxoid fibroma of the sternum. Case report.

We report the second case of chondromyxoid fibroma (CMF) of the sternum, documented in the literature. In this case, only histology of the biopsy was useful in diagnosing CMF before definitive surgery. A wide subtotal resection of the sternum and reconstruction with a Gore-Tex soft tissue patch was performed.

Adult↗
PubMed1993

High malignant surface osteosarcoma arising at the site of a previously treated aneurysmal bone cyst.

A patient who developed a high malignant surface osteosarcoma at the site of a previously treated aneurysmal bone cyst is reported. The patient developed the osteosarcoma 4 years after complete curettage and bone-grafting of the cyst. The clinical, radiological and light microscopic features of this case are described. A causal relationship between the preexisting aneurysmal bone cyst and osteosarcoma is discussed, but seems to be unlikely.

Adult↗
PubMed1993

Analysis of mutant P53 protein in osteosarcomas and other malignant and benign lesions of bone.

Alterations of tumour suppressor genes are considered crucial steps in the development of human cancers. Expressions of p53 protein, a product of the tumour suppressor gene altered most commonly in human cancers examined so far, were investigated immunohistochemically in 18 osteosarcomas and 40 other malignant and benign lesions of bone. A monoclonal antibody clone PAb240, which recognizes a common conformational epitope of mutant p53 proteins, stained nuclei of tumour cells in 12 of 18 osteosarcomas (67%). Six tumours (33%) particularly showed positive immunoreactions in more than half of the tumour cells. PAb240 also stained tumour cells in a small number of other malignant bone tumours, such as malignant fibrous histiocytoma, chondrosarcoma, and Ewing's sarcomas. Furthermore, a small number of cells of giant-cell tumours were positively stained. In contrast, PAb240 was completely negative in 21 benign bone tumours and reactive lesions examined. Another monoclonal antibody clone PAb1801, which reacts with both wild- and mutant-type p53 protein, reacted in nuclei of tumour cells of 7 osteosarcomas (39%). Most of those also reacted with PAb240. PAb1801 was expressed much more frequently in other malignant bone tumours and giant-cell tumours. In addition, PAb1801 showed intranuclear positive reactions in tumour cells of a benign chondroblastoma, and reactive cells such as actively proliferating preosteoblasts in a myositis ossificans and osteoclast-like giant cells in a giant-cell tumour. The immunoelectron-microscopic observation that p53 protein was localized in euchromatic areas of nuclei of osteosarcoma cells supported the specificity of immunoreaction for p53 protein, indicating an active role of p53 protein in the regulation of DNA synthesis and transcription. These findings suggest that point mutation of the p53 gene is frequently involved in the development of osteosarcomas. PAb240 may be a useful tool not only in screening point mutations of the p53 gene in osteosarcomas but also in the differential diagnosis between osteosarcomas and reactive bone-forming lesions. Expressions of mutant p53 protein were not correlated with any clinical or pathological factors examined, although the results should be confirmed in studies of a large number of osteosarcomas.

Adolescent↗
PubMed1993

Prognostic implication of immunodetection of P glycoprotein in Ewing's sarcoma.

Increased expression of P glycoprotein is associated with multidrug resistance in many cell lines. P glycoprotein has been detected in different human tumors. To assess the implication of multidrug resistance in the prognosis of Ewing's sarcoma the expression of P glycoprotein was studied immunohistochemically in pre- and post-therapeutic tumor tissues of 21 cases treated according to the CESS 81 or 86 protocol. The response to chemotherapy was evaluated histologically. Formalin-fixed, paraffin-embedded and fresh frozen sections were immunostained with a monoclonal antibody to P glycoprotein, clone JSB 1, using the double APAAP method. P glycoprotein was detected in 12 cases of 21 (57%) in either pre- or postchemotherapy tumor tissues. From the 21 cases 8 revealed a good morphological response to chemotherapy (33%); 10 of the 13 non-responders were positive for P glycoprotein (77%), but only 2 of the 8 responders (25%). The difference was statistically significant (P < 0.05). Comparing P glycoprotein expression with the clinical outcome, we found that 7 of 12 positive cases had died (58%). From the negative cases only 3 of 9 had died (33%). However, judged by the Kaplan Meyer life tables, these data were not significant. In conclusion our results suggest that the immunodetection of P glycoprotein indicates a poor response to chemotherapy and probably a bad clinical outcome for Ewing's sarcoma patients.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

Spindle cell (leiomyomatous) rhabdomyosarcoma, a rare variant of embryonal rhabdomyosarcoma.

A rare case of the leiomyomatous variant of embryonal rhabdomyosarcoma is reported. A 13-year-old boy presented with a recurrent painless mass on the ventral side of the right forefoot. Microscopically, the tumor consisted of spindle-shaped and round tumor cells in a fascicular or storiform, focally hemangiopericytoma-like growth pattern. The cytoplasm of the spindle-shaped tumor cells was eosinophilic and fibrillary, in some areas resembling smooth muscle cells. Immunohistologically, all tumor cells were vimentin-positive, most of them also stained with antibodies to desmin and muscle specific actin (MSA). In addition, many tumor cells showed a co-expression of alpha-sarcomeric actin and myoglobin. All tumor cells were negative with alpha-smooth muscle actin. Two years after surgical treatment and chemotherapy the patient is well with no evidence of distant metastases. The clinicopathological features and differential diagnostic problems are discussed.

Adolescent↗
PubMed1993

[Aneurysmal bone cyst or giant cell tumor. The value of x-ray diagnosis for differential diagnosis].

Depending on analysis of radiographic morphology, location and patient's age of 72 aneurysmal bone cysts (ABC) and 47 giant cell tumours (GCT), the following criteria suggest an ABC with a high positive predictive value: location in the diaphysis (100%), in the shaft (92%), in the metaphysis or metadiaphysis (86%), patient younger than 17 years (97%) and growth rate grade Lodwick-IA (88%). GCT were selected via the following criteria: epimetaphyseal location (82%) and growth rate grade Lodwick-II (100%). In 14% of the cases, differential diagnosis between both entities is radiologically impossible.

Adolescent↗
PubMed1993

Noncollagenous proteins in heterotopic ossification. Immunohistochemical analysis in 15 paraplegies.

We used immunohistochemical techniques to investigate the distribution pattern of osteonectin, osteocalcin, bone sialoprotein II and the small proteoglycans decorin and PG 100 during different stages of heterotopic ossification (HO) in pressure sores of paraplegic patients. All these noncollagenous proteins (NCPs) accumulated in fibroblasts and preosteoblasts, predominantly in the activity centers of early osteogenetic areas. Mature types of HO showed a more discrete expression pattern for this protein group, with weaker reactions in the narrow osteoblastic rims. Decorin was detected predominantly in the stroma of HO. Our results indicate that the NCPs are important components during the pathogenesis of HO and that fibroblasts may serve as osteoprogenitor cells.

Adult↗